A portable power tool can be a percussion drilling machine, an impact screwdriver, a sabre saw, a sander or the like.
Such power tools have a housing and an electric motor located in the housing. Furthermore, there are located in the housing electric and/or electronic modules, for example, an electric and/or electronic switch, an electronic unit for controlling the electric motor, or the like, the electric and/or electronic module being fastened to one or more receptacles in the housing.
Power tools in particular for mechanical processing of materials, for example, percussion drilling machines and sabre saws, and those for use in fastening technology, for example, impact screwdrivers, are partly subjected to very high mechanical stresses in the form of vibrations which are deliberately generated in order to increase the effectiveness and efficiency of the tool. A vibration-generating device, such as a percussion mechanism, can be used for this purpose in the power tool. Thus, the level or intensity of the percussion amplitude and the magnitude of the percussion acceleration, which also serve as a measure of the efficiency of a percussion drilling machine or of a rotary hammer and/or of a drill bit, are constantly optimized or increased. This in turn increases the demands made on the power tool, on its modules and on its individual parts with regard to resistance and robustness in the face of such pronounced vibrations. Hitherto, microcellular rubber strips have occasionally been pressed between switch and handle shells of the power tool in order to reduce the adverse effects of high vibrations on the power tool. This technique, however, has only been moderately successful.
Vibration resistance is an important technical challenge nowadays, and will become increasingly so in the future. Without further measures with regard to the vibration resistance, severe impairment of the functioning of the power tool, from the release of connections and electrical contacts right through to partial destruction of individual parts may occur. Thus, for example, closed power contacts may lose their contact stability, electronic components may be shaken off or metal heat sinks can become detached from their respective fastenings.